As shown in Figure 3, high levels of serum GGT protein were observed in older (age, >55 years) patients with HCC (P = 0.0395), large tumor size (>5 cm, P = 0343), tumor recurrence (P = 0.0037), and Child Pugh grade (P < 0.001). Here, GGT1 is linked to hepatocellular carcinoma.